Scientific Intelligence. — Chemisiry. 375 



5. Combination of Mercury with metallic wires ^ by M. Kemp 

 (Edinb. Phil. Jour. Apr. 1829.) — When an amalgam of zinc and 

 mercury, containing thirty or fifty times as much mercury as zinc, is 

 covered with a strong solution of muriatic acid, and wires are made 

 to dip into the amalgam, passing through the acid, the quicksilver 

 immediately begins to ascend the wires, and having reached the sur- 

 face of the acid, there stops. It ascends different metals with differ- 

 ent velocities. Wires of platina, copper, iron and zinc, each four 

 inches long, were made to touch the amalgam at the same time ; — 

 the mercury reached the top of the zinc wire in eight minutes, that 

 of the copper in fourteen, and in a little while after, that of the pla- 

 tina and iron. In whatever manner the wire may be contorted, the 

 mercury follows its sinuosities, until it attains the level of the muri- 

 atic acid, which it never surpasses. 



If sufficient time be allowed, the quicksilver not only ascends the 

 wire, but penetrates its substance. There appear no limits to the 

 height to which it may rise, as long as the presence of the acid solu- 

 tion favors its ascension. A stratum of fixed or volatile oil, on the 

 surface of the acid, does not cause the mercury to rise higher. 



The zinc contained in the mercury becomes oxidized, dissolves 

 in the liquid, and in time appears in fine crystals on the surface of the 

 wire. When the action has entirely ceased, the mercury which re- 

 mains at the bottom of the vessel has resumed its primitive purity. 



The cause of this singular phenomenon appears to reside in the 

 opposite electrical states of the amalgam, and the wire in contact with 

 it, the first being positive in relation to the second, but it is difficult 

 to explain in this manner the rapid ascension of the mercury on the 

 zinc wire, which is in the same electrical state as the amalgam, or 

 which at least cannot be negative in relation to it, like the other wires. 



JVote of the Editor, Bib. Univ. — The phrase above in italics, 

 which we have just added to the remark of the author, shews that 

 the phenomenon cannot be attributed to ordinary chemical decompo- 

 sition, arising from Voltaic electricity. The greater rapidity with 

 which the mercury ascends the zinc and copper wires, proves that 

 the facility which metals possess in forming amalgams, favors this as- 

 cension ; nevertheless, the fact cannot be explained by a simple 

 chemical action of mercury on metallic wires, nor by a physical ad- 

 hesion, or a sort of capillary attraction. For if so, why should not 

 the mercury ascend the other wires, which have not the property of 

 forming amalgams, unless with extreme slowness ? The electric cur- 



